The present invention relates to a semiconductor integrated circuit device, and principally to a technique which is effective for use in a RAM (Random Access Memory) mounted so as to mix with various logic circuits.
With advances in semiconductor technology the development of, a large scale integrated circuit is proceeding toward an approach or method for making combinations of large-scaled macros (cores) in a manner similar to the design of a printed circuit board using combinations of parts. A memory is essential to digital signal processing. Particularly since a dynamic RAM has the feature that a large storage capacity is obtained, it plays an important role in the design of the above-described large scale integrated circuit.
A dynamic RAM is typically divided into a plurality of banks, and a read or write operation is performed on each selected bank. Such a method of selecting a bank or a specific region or the like has been described in Japanese Patent Application Laid-Open Nos. Hei 9-245474, 2-83895, 4-313886 and 9-106684.